异常：No WebApplicationContext found: no ContextLoaderListener registered?

No WebApplicationContext found: no ContextLoaderListener registered?
报错应该是spring没正常工作,web.xml里要配的
<servlet>
<servlet-name>SpringContextServlet </servlet-name>
<servlet-class>
org.springframework.web.context.ContextLoaderServlet
</servlet-class>
<load-on-startup>1 </load-on-startup>
</servlet>